The present invention relates to an improved annular fluorescent lamp socket incorporating a starter.
Annular fluorescent lamp sockets (hereinafter referred to merely as "sockets" when applicable) provided integrally with a glow starter have previously been known in the art. In the conventional socket, it is necessary to provide the socket of the glow starter in the socket body itself. This makes the socket body necessarily intricate in construction. Since the glow starter is bulky, it is difficult to miniaturize the socket. Furthermore, the service life of the glow starter is relatively short and therefore it is often necessary to replace it. Because of the starting characteristics of the glow starter, it is required to externally apply light to the glow starter making it necessary that a part of the glow starter protrude from the socket body. Accordingly, the conventional socket suffers from problems that the socket has a poor external appearance and the glow starter can easily be damaged when the fluorescent lamp is replaced.
An annular fluorescent lamp socket has been previously proposed in which, instead of the glow starter, an electronic starter is incorporated in the socket body. In the electronic starter, a high voltage pulse necessary for starting the fluorescent lamp is generated by a ferrite core type pulse transformer coupled to a semiconductor switch. However, that socket has not been put to commercial use because the pulse transformer is considerably bulky and its lamp lighting circuit is intricate with the result that it is difficult to miniaturize the socket and the socket is expensive.